1. Interspecific variation in Rubisco CO 2 /O 2 specificity along the leaf economic spectrum across 23 woody angiosperm plants in the Pacific islands.
- Author
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Sakata T, Matsuyama S, Kawai K, Yasumoto K, Sekikawa S, and Ishida A
- Subjects
- Pacific Islands, Wood, Ribulose-Bisphosphate Carboxylase metabolism, Ribulose-Bisphosphate Carboxylase genetics, Carbon Dioxide metabolism, Plant Leaves metabolism, Phylogeny, Species Specificity, Photosynthesis, Magnoliopsida genetics, Magnoliopsida physiology
- Abstract
The coordinated interspecific variation in leaf traits and leaf lifespan is known as the leaf economic spectrum (LES). The limitation of CO
2 diffusion to chloroplasts within the lamina is significant in C3 photosynthesis, resulting in a shortage of CO2 for Rubisco. Although Rubisco CO2 /O2 specificity (SC/O ) should be adaptively adjusted in response to the interspecific variation in CO2 concentrations [CO2 ] associated with Rubisco, SC/O variations across species along the LES remain unknown. We investigated the coordination among leaf traits, including SC/O , CO2 conductance, leaf protein content, and leaf mass area, across 23 woody C3 species coexisting on an oceanic island through phylogenetic correlation analyses. A high SC/O indicates a high CO2 specificity of Rubisco. SC/O was negatively correlated with [CO2 ] at Rubisco and total CO2 conductance within lamina, while it was positively correlated with leaf protein across species, regardless of phylogenetic constraint. A simulation analysis shows that the optimal SC/O for maximizing photosynthesis depends on both [CO2 ] at Rubisco sites and leaf protein per unit leaf area. SC/O is a key parameter along the LES axis and is crucial for maximizing photosynthesis across species and the adaptation of woody plants., (© 2024 The Authors. New Phytologist © 2024 New Phytologist Foundation.)- Published
- 2024
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